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Graff Diamonds - $65 million

In August 2009, two men in suits entered the Graff Diamonds store in London, England. They brandished their guns and forced the sales staff to unlock the display cases, making off with more than 40 pieces of jewelry worth a total of $65 million U.S..

It was nearly the perfect crime too, because the thieves had visited a makeup artist before entering the store and their appearances were significantly altered so no one could identify them. However, technology turned out to be their downfall. One of the thieves left his cell phone in one of the getaway cars and authorities were able to track him down along with his nine accomplices. While the perpetrators were captured, the jewels were not. To date, none of the stolen jewelry has been recovered.

Schiphol Airport - $77 million

This audacious heist took place on the tarmac at the Schiphol Airport in Amsterdam. Thieves dressed as KLM workers stole an airline vehicle and then hijacked a truck transporting an estimated $77 million ($75 million euros) in diamonds that were being transferred to a plane bound for Antwerp.

Investigators believe the thieves had inside help because they knew when to strike and which vehicle was carrying the diamonds. The thieves have never been caught and the uncut diamonds have never been found.

Antwerp Diamond Center - $100 million

It was the crime that everyone thought would be impossible to pull off. Eighty percent of the world’s uncut diamonds go through Antwerp and many of them are kept in an underground vault below the Antwerp Diamond Center. The vault holds 160 safety deposit boxes where the diamond brokers can leave their gems while negotiating their deals with jewelers.

It took the mastermind of this heist, Leonardo Notarbartolo, four years to assemble his team and plan its perfect execution. The team learned how to bypass the alarm, the routine of the security guard (which tipped them off to where the key to the vault was hidden) and inserted fake tapes into the surveillance system so their activities would not be detected. They had to penetrate eight different levels of security to reach the vault. When they did, there were so many diamonds in the vault that the thieves were only able to empty 123 of the safety deposit boxes. It was the perfect crime…almost.

The thieves were caught when they failed to thoroughly dispose of some uneaten food tossed away with bags from the heist and receipts from the Diamond Center. Most of thieves were caught, but the diamonds have never been found.

Harry Winston - $113 million

Harry Winston jewels are synonymous with the jet-setting rich and famous. His jewels have graced Halle Berry, Elizabeth Taylor, Jennifer Lopez, Madonna, Marilyn Monroe and Angelina Jolie, among many others.

In December 2008, the Harry Winston store in Paris was robbed by three cross-dressing gunmen sporting wigs and skirts as well as guns. They managed to steal $108 million worth of jewels, 297 pieces of jewelry and 104 watches, all in under 20 minutes. The bandits had help from someone on the inside because they referred to employees by name and knew where the store’s secret storage boxes were located according to a report in The Guardian.

The previous year, a team of men dressed as painters had hit the same store, stealing 360 items and 120 watches. The total take between both heists was $113 million. A team of eight men were arrested for the crimes. Only some of the jewels have been recovered.

Intercontinental Carlton Cannes - $136 million

The landmark hotel was the backdrop for the 1955 film, “To Catch a Thief,” starring Cary Grant and Grace Kelly, and over the years the hotel has been the site of several real life jewel heists. But none was as quickly and efficiently executed as one by a single thief in July 2013.

The jewels were part of a collection belonging to the Dubai-based Leviev diamond house. At the time of the theft they were being stored in what turned out to be a very poorly guarded hotel room. The lone robber wore a bandana over his face and a motorcycle helmet, and was armed with an automatic pistol. The exhibit had not yet opened and the jewels were not in their secure display cases. Several people were in the room at the time, including three unarmed private security guards.

The thief took a briefcase and what is described as a “box of jewels” that contained 72 pieces including flawless colorless diamonds, pink and yellow diamonds, emeralds and sapphires in less than a minute and escaped out a side door.

While the thief operated alone, authorities believed he had accomplices because of the perfect timing of the heist and the ease with which he escaped. No one has seen the thief or the jewels since.

While the jewelry most insureds own probably doesn’t rise to the value of the gems highlighted here, it’s still wise to ensure that major pieces of jewelry are protected by insurance. According to the Insurance Information Institute, jewelry losses are the most frequent contents claims, so here are some tips to protect your beautiful gems:

1. Contact your insurer to see if any pieces of jewelry need additional insurance. Some policies have limits of $1,000 to $2,000.
2. When purchasing jewelry, send a copy of the receipt to the insurer along with a photo of the piece. If it is a gift, have it appraised and send the appraisal to the insurer.
3. Keep a home inventory of all possessions, especially jewelry and collectibles.

Jewelry should definitely be enjoyed and cherished, and properly insuring it against loss allows the wearer to appreciate it even more.